Mercedes has announced it is to equip all of its diesel passenger cars with a particulate filter as standard.

The company claims to be the first automobile manufacturer to take the step which will reduce levels of pollution and curb harmful emissions.

The diesel initiative initially applies in Germany, Austria, the Netherlands and Switzerland, with other European countries to follow.

The particulate filter system developed by Mercedes-Benz is maintenance-free and operates without additives. The filter is regenerated by appropriate adjustment of various engine functions.

Mercedes is currently showcasing its technology at the Geneva Motor Show, where it is attempting to show leadership in the field of car diesel engines.

"Nowadays our diesels are as powerful and sporty as the very latest petrol units. At the same time they offer more torque and are particularly economical, environmentally friendly and smooth," said Dr Eckhard Cordes, head of the Mercedes car group Cordes.

Around 56 per cent of all Mercedes passenger cars in western Europe are ordered with a diesel engine, meaning the move will have a significant reduction on emissions from Mercedes cars.

The move comes shortly after the Chartered Society of Physiotherapy found that diesel emissions posed a serious public health threat in the UK, more serious than had previously been realised.